I am totally making this up as I go and switching plans mid-stream! I have a good idea what the end shape of this board is suppose to be but the thought process is backwards; instead of carving the board out of a chunk of material I'm having to build it up with as little material as possible. I got in a good six hours in the garage today - excellent way to level the emotional keel FYI - changing my approach from what I had conceived last night. Instead of a central stringer with ribs coming off it, I've moved to twin stringers with central cross members to make a structural ladder. This has been shaped, had all the lightening holes cut in it and fitted with the cross members. I switched from gorilla glue which I used on the bottom to epoxy and glued the central structure in. It will sit until tomorrow afternoon before I can get back at it - plenty of time for the epoxy to cure and for me to come up with the next detail.